The invention relates to a motor vehicle door lock, with a locking mechanism mainly consisting of a catch and a pawl, furthermore with a release lever to lift the pawl and thus open the locking mechanism and with an accumulator element actuated by a spring, which maintains the pawl in a raised position until the catch is completely or almost completely open.
A so-called buffer or buffer lever function in motor vehicles is typically executed on the rear motor vehicle door lock, i.e. the tailgate latch. With the aid of the buffer lever function, it is finally ensured that when the locking mechanism is open the pawl is not unintentionally engaged again or cannot intentionally be engaged with the catch. In practice, such situations are observed, for example, if the tailgate belonging to the tailgate latch is not completely opened or cannot be completely opened due to snow loads or other stresses.
In actual fact, in practice there is the risk of the locking mechanism not opening further than the pre-ratchet and the catch engaging again. The pertaining motor vehicle door latch thus needs to be reopened in order to be able to completely open the tailgate in the example case.
In order to manage such functional states, the generic state of the art in accordance with EP 1 862 618 B1 proposes that the buffer element is held at at least one latch component with the aid of the spring when the adjacent locking mechanism is opened. Thus, overall, the functional safety will be increased and a design with a simple construction will be provided.
In the further state of the art in accordance with US 2011/0031765 A1 a buffer element is provided for which is connected to a housing component. The buffer element has a stopper which interacts with a hook on the pawl in order to maintain this in an open position. If, during opening of the locking mechanism, the catch goes into its completely open position, a finger attached to the catch ensures that the buffer element is lifted from the pawl. Subsequently, the pawl glides along the catch and can no longer engage into the pre-ratchet.
The state of the art has fundamentally been proven, but can be improved. It is therefore evident in view of the EP 1 862 618 B1 that the buffer element and spring are separated from one another which increases technological expenditure and makes installation harder. Although US 2001/031765 A1 works here with a constructional unit from the buffer element and the spring so to speak, this acts on the pawl, however. Thus, a relatively discharging construction is followed. Because both the known buffer element and the locking mechanism consisting of a catch and a pawl are arranged at levels spaced apart.
If we now additionally still want to install the release lever, including the drive, a third level is typically required which increases the construction volume. However, nowadays motor vehicle door latches are required with compact dimensions and few functional components in order on the one hand to be able to use the limited available installation space inside a motor vehicle door and on the other hand to take into account the enormous price pressure. This is where the invention wishes to provide assistance.